For those looking to simply enjoy the run, going out and running whatever feels good on that day is a great plan.
However, for anyone looking to seriously improve upon their running fitness, proper planning and progression must be taken in to account.
Simply going out and running will only get you so far in the way of PRs and the time will come when this "plan" will stop working. The day this happens is the day you are no longer a newb.
Here's what comes next:
This is likely ...